apt: Add autoremove and auto-remove commands

cmdline/apt.cc

@@ -55,6 +55,7 @@ static bool ShowHelp(CommandLine &)
       "\n"
       " install - install packages\n"
       " remove  - remove packages\n"
+      " autoremove - Remove automatically all unused packages\n"
       "\n"
       " upgrade - upgrade the system by installing/upgrading packages\n"
       " full-upgrade - upgrade the system by removing/installing/upgrading packages\n"
@@ -76,6 +77,8 @@ int main(int argc, const char *argv[])					/*{{{*/
                                    // package stuff
                                    {"install",&DoInstall},
                                    {"remove", &DoInstall},
+                                   {"autoremove", &DoInstall},
+                                   {"auto-remove", &DoInstall},
                                    {"purge", &DoInstall},
 
                                    // system wide stuff

doc/apt.8.xml

@@ -86,6 +86,11 @@
      installed instead of removed.</para></listitem>
      </varlistentry>
 
+     <varlistentry><term><option>autoremove</option> (and the <option>auto-remove</option> alias since 1.1)</term>
+     <listitem><para><literal>autoremove</literal> is used to remove packages that were automatically
+     installed to satisfy dependencies for other packages and are now no longer needed.</para></listitem>
+     </varlistentry>
+
      <varlistentry><term><option>edit-sources</option></term>
      <listitem><para><literal>edit-sources</literal> lets you edit
      your sources.list file and provides basic sanity checks.